Fuse



p 3, 1938. E. J. HOTTINGER 2,129,692

FUSE

Filed 001:. l, 1937 2 Sheets-Sheet 1 I'nventu: Edwin J Hutting Er Attorney Sept. 13, 1938. E HoTTlNGER 2,129,692

FUSE

Filed Oct. 1, 1937 2 Sheets-Sheet 2 Patented Sept. 13, 1938 UNITED STATES .ATET OFFICE Application October 1,

9 Claims.

1937, Serial No. 166,771

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) The inventiondescribed herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a fuse.

The purpose of the inventionis to provide a bore safe and detonator safe fuse for mortar ammunition which may be set for instantaneous or delay action on impact but will not function upon contact with light obstructions such as camouflage.

The fuse is characterized principally by a simple and novel arrangement for controlling the operation of a rotor carrying the instantaneous and delay powder trains and by a delayed arming firing mechanism whose elements are normally disconnected and are only brought into operative association during flight of the projectile.

To these and other ends, theinvention consists in the construction, arrangement and combination of elements described hereinafter and pointed out in the claims forming a part of this specification.

A practical embodiment of the invention is illustrated in the accompanying drawings,

wherein:

Fig. 1 is a longitudinal sectional view of the improved fuse showing the parts in the safe or unarmed position.

'Figs.2 and 3 are sectional views on the corresponding lines of Fig. 1.

Fig. 4 is a perspective View of the key.

Fig. 5 is a fragmentary view in side elevation of a portion of the fuse casing.

Fig. 6 is a longitudinal sectional view of the fuse with theparts in armed position.

Fig. 7 is a sectional view on the line 'l'l of Fig. 6.

Fig. 8 is Fig. 2.

Figs. 9 and 10 are views in side elevation of the rotor and Fig. 11 is a plan View of the rotor.

Fig. 12 is a sectional fragmentary detail view.

The fuse casing consists of a body 5, a nose 6 threaded in the front end of the body, a plate 1 closing the rear end of the body and attached theretoa-nd a cup 9 threaded to the plate. A booster charge In in the central portion of the plate and a similar charge In eccentrically of the plate arein communication with a main charge H contained. in the cup 9.

The body 5 is formed with a cavity l2 for .housing arotor 13 which is rotatable about a a sectional view on the line 8-8 of pin I4 mounted eccentrically in the body. A torsion spring 15 housed in a recess in the body has one end anchored in the body and the other end anchored in the rotor. A pair of powder trains I6 and I1 including primers, and respectively affording instantaneous and delay action, are

arranged in the rotor equidistantly and at such distance from its center so that they may be successively brought into alignment with the center of the fuse upon rotation of the rotor. The train I1 is adapted to fire through the train 16 which has an outlet [6 The rotor is normally held in the safe or unarmed position against the action of the spring I5 by means of a firing pin [8 which is removably inserted in a recess IS in the rotor and also by means of a key 20. The key has a cylindrical shank 2| rotatably mounted in an aperture 22 in the body and is held against axial displacement by an annular flange .23 lWhlCh is confinedbetween a shoulder 24 and a spring washer 25 held by a nut 26 threaded in the body. The outer end of the key is formed with a slot 21 whereby it may be turned with a tool applied exteriorally of the fuse. The inner portion of the key is formed into a segment 28 and on the inner end of the segment there is an extended finger 29 disposed eccentrically of thekey.

The finger 29 is disposed in an annular groove 30 formed in the rotor. As shown in Figs. 9 30 and 10 and 11 the groove is cut so as to provide three stop shoulders 3|, 32, 33, which are stepped from the end face of the rotor and are spaced circumferentially.

The shoulders have definite angular relationships with respect to the recess I9 and the powder trains l6 and I! so that these elements will be positioned axially of the fuse and in line with the firing pin when the shoulders 3|, 32, and 33 are engaged, in the order named, by the finger 29. In order that the angular position of the finger may be indicated on the exterior of the fuse, the outer end face of the key is marked with an index 34 (Fig. 5) which is readable against appropriate inscriptions on the outside of the body.

Referring to Fig. 5, when the index points to the inscription Safe, the finger 29 is disposed as shown in dotted lines in this figure and in full lines in Fig. 1. Rotation of the key through 90 with the index pointing at Inst moves the, finger into the path of the shoulder 32 to set the fuse for instantaneous action and rotation through 180 withthe index pointing at Del moves the finger into the path of the shoulder 33 to set the fuse for delay action.

The body 5 is provided with a passage 35 extending from its front end to the cavity E2. The firing pin it placed in the inner end of the passage is of such length that it will extend into the recess iii of the rotor when a head is on its outer end is seated on a shoulder 36 in the passage. A spring 371 acting on the head 98 normally urges the firing pin out of engagement with the rotor. A tube 38 movably mounted in the passage engages the head i3 of the firing pin and is formed at its outer end with a socket 39.

The tube is held in the safe or unarmed position to maintain the firing pin in the recess IQ of the rotor by means of a pin 43 which is slidably mounted in a transversely disposed passage M in the bolt and extends through an aperture 42 in the tube. This pin also serves to hold a block 53 in the inner end of the tube. The pin is held in engagement with the tube and against the action of a spring 4d tending to withdraw it by means of a set-back pin The pin is arranged longitudinally of the fuse and normally it has one end interposed in the path of the pin it] and the other end resting on the segment 28 of the key. A spring iii seated on the base of a thimble il'i threaded in the body acts on a collar 38 on the set-back pin 45 to hold the collar against the body and maintain the set-back pin in position to oppose withdrawal of the pin 49. The pin 55 can only be moved rearwardly under the influence of set-back when the projectile is fired after the key has been rotated to displace the segment.

The nose 6 is formed with a counterbored passage for slidably receiving a striker A spring 59 embracing the striker and seated on a shoulder 56 acts on the striker head 52 to normally hold the striker in the forward position, the movement of the striker under the influence of the spring being limited by a ring which is placed on the grooved inner end of the striker and engages a shoulder 5 3 in the nose. A thin cover plate $5 for excluding foreign substances and for preventing functioning of the striker on contact with light obstructions employed in camoufiages is secured on the front edge of the nose in any convenient manner.

The fuse is safe or unarmed when the parts are in the position shown in Fig. 1, the rotor being positively held to maintain the powder trains out of alignment with the axis of the fuse, and the striker and the firing pin being incapable of operative association. The fuse cannot be armed as shown in Fig. 2 until the key Ed is turned either to the instantaneous or delay setting and the firing pin withdrawn from the rotor, both of these operations being necessary to permit rotation of the rotor. The firing pin, however, cannot be withdrawn from the rotor until the projectile has been fired and the set-back pin Q5, no longer opposed by the segment of the key, is free to move to the rear and release the pin at which in turn releases the tube 38 and the firing pin.

Upon withdrawal of the pin dd, the spring 3"? moves the firing pin and the tube 33 forwardly until the tube engages the inner face of the nose. As soon as the rotor is released it is rotated until arrested by the key. In the setting which. places the delay element in operative position (Fig. 2) it is necessary to provide some means for holding the rotor in place after impact. This is accomplished in a well known manner by means of a plunger 5% (Fig. 12) which is carried by the plate I and at the proper time enters a recess 51 in the rotor.

During the fiight of the projectile, the block 43 moves forwardly being acted on by creep force and gravity as the projectile descends and finally lodges in the socket 39 where it assumes such a position as to establish a connection between the tube 38 and the striker 49 so that on impact the movement of the striker will be transmitted through the tube to the firing pin. Should the block, by any chance, assume such a position that it could reenter the bore of the tube, then it would be driven inwardly and directly actuate the firing pin.

In the instantaneous setting the powder train i 6 fires directly to the booster ill and in the delay setting the powder train ll fires through the train i6 and then to the booster Ill I claim:

1. In a fuse, a body, a rotor mounted in the body and having a recess, a spring for rotating the rotor, a plurality of powder trains carried by the rotor, a plurality of circumferentially spaced and stepped stops on the rotor and having a definite angular relationship with the recess and the powder trains, a rotatable key in the body having a segmental portion and a finger extend,- ing therefrom, said key adapted on rotation to present its finger selectively in the path of the stops, a firing pin in the body and normally extending into the recess of the rotor, a spring normally tending to withdraw the firing pin, a member for holding the firing pin in engagement with the rotor, a pin in the body and engaging said member to hold it in place, a spring normally tending to withdraw the pin, a set-back pin in the body, a spring normally tending to hold the set-back pin in position to oppose withdrawal of the pin, and the segment of the key adapted in one position of setting of the key to oppose withdrawal of the set-back pin.

2. In a fuse, a body, a rotor mounted in the body and having a recess, a spring for rotating the rotor, a plurality of powder trains carried by the rotor, a plurality of circumferentially spaced and stepped stops on the rotor and having a definite angular relationship with the recess and the powder trains, a rotatable key in the body having a finger, said key adapted on rotation to present its finger selectively in the path of the stops, a firing pin in the body and normally extending into the recess of the rotor, a spring normally tending to withdraw the firing pin, a member for holding the firing pin in engagement with the rotor, a pin in the body and engaging said member to hold it in place, a spring normally tending to withdraw the pin, and means operable on set back for controlling withdrawal of the pin.

3. In a fuse, a body, a rotor mounted in the body and having a recess, a spring for rotating the rotor, a plurality of powder trains carried by the rotor, a plurality of circumferentially spaced and stepped stops on the rotor and having a definite angular relationship with the recess and the powder trains, a rotatable key in the body having a finger, said key adapted on rotation to present its finger selectively in the path of the stops, a firing pin in the body and normally extending into the recess of the rotor, a spring normallytending to withdraw the firing pin, and means operable during fiight for controlling withdrawal of the firing pin from the rotor.

4. In a fuse, a body, a rotor mounted in the body and having a recess, a spring for rotating the rotor, a plurality of powder trains carried by the rotor, a plurality of circumferentially spaced and stepped stops on the rotor and having a definite angular relationship with the recess and the powder trains, a rotatable key in the body having a segmental portion and a finger extending therefrom, said finger adapted on rotation to present its finger selectively in the path of the stops, a firing pin in the body and normally extending into the recess of the rotor, a spring normally tending to Withdraw the firing pin, and means for controlling withdrawal of the firing pin and including a member normally held against movement by the segment of the key.

' "5. In a fuse, a'body, a rotor mounted in the body, said rotor formed with a groove providing a plurality of stepped and circumferentially spaced stop shoulders, elements of a plurality of firing mechanisms in the rotor, a spring for rotating the rotor, a rotatable key in the body and having an eccentric finger disposed in the groove of the rotor, said finger selectively positionable in the path of the stop shoulders to control the amount of rotation of the rotor.

6. In a fuse, a body, a rotor mounted in the body, elements of a plurality of firing mechanisms in the rotor, a plurality of circumferentially spaced and stepped stops on the rotor, a spring for rotating the rotor, a rotatable key in the body and having an eccentric finger selectively positionable in the path of the stops to control the amount of rotation of the rotor.

'7. In a fuse, a casing having a passage, a firing pin in the passage, a spring for moving the firing pin forwardly in the passage, a tube in the passage having its inner end engaging the firing pin and having a socket on its outer end, a

block normally in the inner end of the tube but movable during flight to lodge in the socket thereof, a pin in the casing and engaging the tube and block to hold these members and the firing pin against forward movement, a spring normally tending to withdraw the pin, a setback pin in the body for opposing withdrawal of the pin, a manually set key adapted in one position to oppose withdrawal of the set-back pin, and a striker mounted in the front of the casing and adapted on impact to engage the block.

8. In a fuse, a casing having a passage, a firing pin in the passage, a spring for moving the firing pin forwardly in the passage, a tube in the passage h-aving its inner end engaging the firing pin and having a socket on its outer end, a block normally in the inner end of the tube but movable during flight to lodge in the socket thereof, means engaging the tube and block to hold these members and the firing pin against forward movement, said means movable to releasing position during flight, and a striker mounted in the front of the casing and adapted on impact to engage the block and drive the tube rearwardly.

9. In a fuse, a casing, a tube mounted in the casing for longitudinal movement and having a socket on its forward end, a spring normally tending to move the tube forwardly, a block in the inner end of the tube and movable during fiight to lodge in the socket of the tube, means releasable during flight for holding the tube and block against forward movement, and a striker mounted in the front of the casing and adapted on impact to engage the block and drive the tube rearwardly.

EDWIN J. I-IOTTINGER. 

